80691988 has 24 divisors (see below), whose sum is σ = 152864712. Its totient is φ = 37048704.

The previous prime is 80691983. The next prime is 80691991. The reversal of 80691988 is 88919608.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 8305924 + 72386064 = 2882^2 + 8508^2 .

It is a super-2 number, since 2×80691988² = 13022393854784288, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (80691983) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6306 + ... + 14182.

It is an arithmetic number, because the mean of its divisors is an integer number (6369363).

Almost surely, 2^80691988 is an apocalyptic number.

It is an amenable number.

80691988 is a deficient number, since it is larger than the sum of its proper divisors (72172724).

80691988 is a wasteful number, since it uses less digits than its factorization.

80691988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8091 (or 8089 counting only the distinct ones).

The product of its (nonzero) digits is 248832, while the sum is 49.

The square root of 80691988 is about 8982.8719238337. The cubic root of 80691988 is about 432.1257421461.

The spelling of 80691988 in words is "eighty million, six hundred ninety-one thousand, nine hundred eighty-eight".